JP4774996B2 - Radiation sensitive resin composition - Google Patents

Description

  The present invention relates to a radiation sensitive resin composition suitable for fine processing. In particular, the present invention relates to a positive radiation-sensitive resin composition suitable for forming a fine pattern with an electron beam (hereinafter abbreviated as EB), X-rays, or extreme ultraviolet rays (hereinafter abbreviated as EUV).

  In the field of microfabrication represented by the manufacture of integrated circuit elements, in order to obtain a higher degree of integration of integrated circuits, miniaturization of design rules in lithography is progressing rapidly, and microfabrication is performed stably. The development of lithography processes that can do this is strongly promoted. However, since it is difficult to form a fine pattern of 100 nm or less with high accuracy by the conventional method using KrF or ArF excimer laser, a method using EB or EUV has been proposed.

Various types of radiation-sensitive resin compositions used as such positive resist materials for electron beams or extreme ultraviolet rays used in such ultrafine processing have been proposed.
(1) A methacrylic main chain-cutting radiation sensitive resin composition such as PMMA (polymethyl methacrylate):
Although the resolution is excellent, there are problems in etching resistance and sensitivity, and it is difficult to put it to practical use. Poly t-butyl α-chloromethylstyrene (see Patent Document 1) having a good balance between resolution and sensitivity, and patent application (see Patent Document 2) in which atoms (N, O, S) that are easily cut by an electron beam are introduced at the resin terminal ) Has been. However, although improvement in sensitivity is recognized, sensitivity and etching resistance have not reached a practical level.
(2) Chemically amplified radiation-sensitive resin composition having polyhydroxystyrene resin (resin for KrF excimer) and novolak (resin for i-line) partially protected with an acid-dissociable functional group and an acid generator:
Excellent balance of sensitivity, resolution and etching resistance, partially acetal protected polyhydroxystyrene resin + acid generator (see Patent Document 3), various acid dissociable partially protected polyhydroxystyrene resins + fluorine-containing aromatic sulfonic acid generated onium salt + Fluorine-based or silicon-based surfactant (see Patent Document 4), onium salt having at least one electron-withdrawing group (F, cyano group, nitro group) as a cation moiety substituent (see Patent Document 5), disulfonyl group Various patents have been filed, such as a resin having an N-oxyimide sulfonyl group (see Patent Document 7), and the like. However, the film surface roughness (hereinafter referred to as roughness), sensitivity, and resolution at the time of forming a fine pattern has not reached a practical level.
In particular, when patterning using a KrF excimer laser, if the acid generator exceeds about 20 parts by weight with respect to 100 parts by weight of the acid-dissociable group-containing resin, the sensitivity is improved but the pattern shape is reduced, There are problems such as worsening of roughness.

JP 2000-147777 A JP 11-29612 A JP-A-6-194842 JP 2000-187330 A JP 2001-075283 A JP 2002-072483 A JP 2002-107920 A

The present invention has been made to address the above problems, and is a positive radiation-sensitive resin composition that is excellent in line roughness, etching resistance, sensitivity, resolution, and can form a fine pattern with high accuracy and stability. The purpose is to provide goods.
A further object of the present invention is to provide a chemically amplified positive radiation-sensitive resin composition suitable for EB, X-rays and EUV, which is effectively sensitive to electron beams or extreme ultraviolet rays.

（式（１）において、Ｒ¹は水素原子またはメチル基を表し、Ｒ²は１価の有機基を表し、ｓは１〜３の整数であり、ｔは０〜３の整数であり、複数存在するＲ²は相互に同一でも異なってもよく、また、式（３）において、Ｒ⁶は水素原子またはメチル基を表し、Ｒ⁷はｔ−ブチル基、１−メチル−１−シクロペンチル基、１−エチル−１−シクロペンチル基を表す） The radiation-sensitive resin composition of the present invention has a radiation-sensitive acid generator (hereinafter abbreviated as an acid generator) (A) and is alkali-insoluble or alkali-insoluble and easily soluble in alkali by the action of an acid. A positive radiation sensitive resin composition comprising an acid dissociable group-containing resin (B) and an acid diffusion controller (C) and patterned using EB, X-rays or EUV, wherein the acid dissociation The acid generator (A) is 20 to 80 parts by weight and the acid diffusion controller (C) is 0.1 to 1 part by weight with respect to 100 parts by weight of the functional group-containing resin (B). It is characterized by being included below.
The acid generator (A) is at least one compound selected from a sulfonyloxyimide compound, a sulfonium salt compound, an iodonium salt compound, and a diazonium salt compound.
The acid dissociable group-containing resin (B) includes a repeating unit represented by the following formula (1) and a repeating unit represented by the following formula (3).

(In Formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a monovalent organic group, s is an integer of 1 to 3, t is an integer of 0 to 3, R ² present may be the same as or different from each other. In Formula (3), R ⁶ represents a hydrogen atom or a methyl group, R ⁷ represents a t-butyl group, a 1-methyl-1-cyclopentyl group, Represents a 1-ethyl-1-cyclopentyl group)

  When the positive radiation sensitive resin composition of the present invention is patterned using EB, X-rays or EUV, the acid generator (A) is 20 to 80 parts by weight and the acid diffusion controller Since (C) is contained in an amount of 0.1 parts by weight or more and 1 part by weight or less, the line roughness, etching resistance, sensitivity, and resolution are excellent, and a fine pattern can be formed with high accuracy and stability.

Hereinafter, embodiments of the present invention will be described in detail.
Acid generator (A)
Examples of the acid generator (A) that generates acid upon irradiation with EB and EUV include onium salt compounds such as sulfonyloxyimide compounds, sulfonium salt compounds and iodonium salt compounds, sulfone compounds, sulfonic acid ester compounds, diazonium salt compounds, Examples include sulfonylmethane compounds, oxime sulfonate compounds, hydrazine sulfonate compounds, and the like.
Among these, at least one compound selected from a sulfonyloxyimide compound, a sulfonium salt compound, an iodonium salt compound, and a diazonium salt compound is preferable for EB, X-ray, and EUV because line roughness characteristics are improved. .

（式（４）において、Ｒ⁸はアルキレン基、アリーレン基、アルコキシレン基等の２価の基を表し、Ｒ⁹はアルキル基、アリール基、ハロゲン置換アルキル基、ハロゲン置換アリール基等の１価の基を表す） Examples of the sulfonyloxyimide compound include a compound represented by the following formula (4).

(In Formula (4), R ⁸ represents a divalent group such as an alkylene group, an arylene group, or an alkoxylen group, and R ⁹ represents a monovalent group such as an alkyl group, an aryl group, a halogen-substituted alkyl group, or a halogen-substituted aryl group. Represents the group of

  Specific examples of the sulfonyloxyimide compound include N- (trifluoromethanesulfonyloxy) succinimide, N- (trifluoromethanesulfonyloxy) phthalimide, N- (trifluoromethanesulfonyloxy) diphenylmaleimide, N- (trifluoromethanesulfonyloxy) bicyclo. [2.2.1] Hept-5-ene-2,3-dicarboximide, N- (trifluoromethanesulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide, N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (trifluoromethanesulfonyloxy) naphthylimide, N- (10-camphorsulfonylo Succinimide, N- (10-camphorsulfonyloxy) phthalimide, N- (10-camphorsulfonyloxy) diphenylmaleimide, N- (10-camphorsulfonyloxy) bicyclo [2.2.1] hept-5-ene- 2,3-dicarboximide, N- (10-camphorsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (10-camphorsulfonyl) Oxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (10-camphorsulfonyloxy) naphthylimide, N-{(5-methyl-5-carboxymethyl) Bicyclo [2.2.1] heptan-2-yl) sulfonyloxy} succinimide,

N- (n-octanesulfonyloxy) succinimide, N- (n-octanesulfonyloxy) phthalimide, N- (n-octanesulfonyloxy) diphenylmaleimide, N- (n-octanesulfonyloxy) bicyclo [2.2.1 ] Hept-5-ene-2,3-dicarboximide, N- (n-octanesulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (n-octanesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (n-octanesulfonyloxy) naphthylimide, N- (4- Toluenesulfonyloxy) succinimide, N- (4-toluenesulfonyloxy) phthalimide, N- (4-toluenes) Phonyloxy) diphenylmaleimide, N- (4-toluenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (4-toluenesulfonyloxy) -7-oxabicyclo [2.2.1] Hept-5-ene-2,3-dicarboximide, N- (4-toluenesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3- Dicarboximide, N- (4-toluenesulfonyloxy) naphthylimide,

N- (2-trifluoromethylbenzenesulfonyloxy) succinimide, N- (2-trifluoromethylbenzenesulfonyloxy) phthalimide, N- (2-trifluoromethylbenzenesulfonyloxy) diphenylmaleimide, N- (2-trifluoro Methylbenzenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (2-trifluoromethylbenzenesulfonyloxy) -7-oxabicyclo [2.2.1 ] Hept-5-ene-2,3-dicarboximide, N- (2-trifluoromethylbenzenesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide N- (2-trifluoromethylbenzenesulfonyloxy) naphthylimi N- (4-trifluoromethylbenzenesulfonyloxy) succinimide, N- (4-trifluoromethylbenzenesulfonyloxy) phthalimide, N- (4-trifluoromethylbenzenesulfonyloxy) diphenylmaleimide, N- (4-tri Fluoromethylbenzenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (4-trifluoromethylbenzenesulfonyloxy) -7-oxabicyclo [2.2. 1] Hept-5-ene-2,3-dicarboximide, N- (4-trifluoromethylbenzenesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboxy Imido, N- (4-trifluoromethylbenzenesulfonyloxy) naphthyl Bromide,

N- (perfluorobenzenesulfonyloxy) succinimide, N- (perfluorobenzenesulfonyloxy) phthalimide, N- (perfluorobenzenesulfonyloxy) diphenylmaleimide, N- (perfluorobenzenesulfonyloxy) bicyclo [2.2.1] ] Hept-5-ene-2,3-dicarboximide, N- (perfluorobenzenesulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (perfluorobenzenesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (perfluorobenzenesulfonyloxy) naphthylimide, N- (1- Naphthalenesulfonyloxy) succinimide, N- (1-na Talensulfonyloxy) phthalimide, N- (1-naphthalenesulfonyloxy) diphenylmaleimide, N- (1-naphthalenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N -(1-Naphthalenesulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (1-naphthalenesulfonyloxy) bicyclo [2.2.1 ] Heptane-5,6-oxy-2,3-dicarboximide, N- (1-naphthalenesulfonyloxy) naphthylimide,

N- (nonafluoro-n-butanesulfonyloxy) succinimide, N- (nonafluoro-n-butanesulfonyloxy) phthalimide, N- (nonafluoro-n-butanesulfonyloxy) diphenylmaleimide, N- (nonafluoro-n-butanesulfonyloxy) ) Bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (nonafluoro-n-butanesulfonyloxy) -7-oxabicyclo [2.2.1] hept-5 Ene-2,3-dicarboximide, N- (nonafluoro-n-butanesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (nonafluoro- n-butanesulfonyloxy) naphthylimide, N- (perfluoro-n-octanesulfo Ruoxy) succinimide, N- (perfluoro-n-octanesulfonyloxy) phthalimide, N- (perfluoro-n-octanesulfonyloxy) diphenylmaleimide, N- (perfluoro-n-octanesulfonyloxy) bicyclo [2.2 .1] Hept-5-ene-2,3-dicarboximide, N- (perfluoro-n-octanesulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide, N- (perfluoro-n-octanesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (perfluoro-n-octane Sulfonyloxy) naphthylimide,

N- (benzenesulfonyloxy) succinimide, N- (benzenesulfonyloxy) phthalimide, N- (benzenesulfonyloxy) diphenylmaleimide, N- (benzenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2 , 3-dicarboximide, N- (benzenesulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (benzenesulfonyloxy) bicyclo [2 2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (benzenesulfonyloxy) naphthylimide and the like.

  Among these sulfonyloxyimide compounds, N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (10-camphorsulfonyloxy) succinimide, N- (4-toluenesulfonyloxy) succinimide, N- (nonafluoro-n-butanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (benzenesulfonyloxy) ) Bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-{(5-methyl-5-carboxymethylbicyclo [2.2.1] heptan-2-yl) sulfonyl Oxy} succinimide and the like are preferable because they improve the line roughness characteristics.

  Examples of the sulfonium salt compounds include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, triphenylsulfonium pyrenesulfonate, triphenylsulfonium n-dodecylbenzenesulfonate. , Triphenylsulfonium 4-toluenesulfonate, triphenylsulfonium benzenesulfonate, triphenylsulfonium 10-camphorsulfonate, triphenylsulfonium n-octanesulfonate, triphenylsulfonium 2-trifluoromethylbenzenesulfonate, triphenylsulfonium 4-trifluoromethyl Benzene sulfonate, triphenyl Rufonium hexafluoroantimonate, triphenylsulfonium naphthalenesulfonate, triphenylsulfonium perfluorobenzenesulfonate, (4-t-butylphenyl) diphenylsulfonium trifluoromethanesulfonate, (4-t-butylphenyl) diphenylsulfonium nonafluoro-n- Butanesulfonate, (4-t-butylphenyl) diphenylsulfonium perfluoro-n-octanesulfonate, (4-t-butylphenyl) diphenylsulfonium pyrenesulfonate, (4-t-butylphenyl) diphenylsulfonium n-dodecylbenzenesulfonate, (4-t-butylphenyl) diphenylsulfonium 4-toluenesulfonate, (4-t-butylphenyl) diphenylsulfate Nitrobenzenesulfonate, (4-t-butylphenyl) diphenylsulfonium 10-camphor-sulfonate, (4-t-butylphenyl) diphenylsulfonium n-octanesulfonate, (4-t-butylphenyl) diphenylsulfonium 2-trifluoromethyl Benzenesulfonate, (4-t-butylphenyl) diphenylsulfonium 4-trifluoromethanebenzenesulfonate, (4-t-butylphenyl) diphenylsulfonium perfluorobenzenesulfonate,

(4-t-butoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, (4-t-butoxyphenyl) diphenylsulfonium nonafluoro-n-butanesulfonate, (4-t-butoxyphenyl) diphenylsulfonium perfluoro-n-octanesulfonate, (4-t-butoxyphenyl) diphenylsulfonium pyrenesulfonate, (4-t-butoxyphenyl) diphenylsulfonium n-dodecylbenzenesulfonate, (4-t-butoxyphenyl) diphenylsulfonium 4-toluenesulfonate, (4-t-butoxy Phenyl) diphenylsulfonium benzenesulfonate, (4-t-butoxyphenyl) diphenylsulfonium 10-camphor-sulfonate, (4-t-butoxypheny ) Diphenylsulfonium n-octanesulfonate, (4-t-butoxyphenyl) diphenylsulfonium 2-trifluoromethylbenzenesulfonate, (4-t-butoxyphenyl) diphenylsulfonium 4-trifluoromethylbenzenesulfonate, (4-t-butoxy) Phenyl) diphenylsulfonium perfluorobenzenesulfonate, (4-hydroxyphenyl) diphenylsulfonium trifluoromethanesulfonate, (4-hydroxyphenyl) diphenylsulfonium nonafluoro-n-butanesulfonate, (4-hydroxyphenyl) diphenylsulfonium perfluoro-n- Octanesulfonate, (4-hydroxyphenyl) diphenylsulfonium pyrenesulfonate, (4-hydroxyphene L) Diphenylsulfonium n-dodecylbenzenesulfonate, (4-hydroxyphenyl) diphenylsulfonium 4-toluenesulfonate, (4-hydroxyphenyl) diphenylsulfoniumbenzenesulfonate, (4-hydroxyphenyl) diphenylsulfonium 10-camphor-sulfonate, (4 -Hydroxyphenyl) diphenylsulfonium n-octanesulfonate, (4-hydroxyphenyl) diphenylsulfonium 2-trifluoromethylbenzenesulfonate, (4-hydroxyphenyl) diphenylsulfonium 4-trifluoromethylbenzenesulfonate, (4-hydroxyphenyl) diphenyl Sulfonium perfluorobenzene sulfonate,

Tris (4-methoxyphenyl) sulfonium trifluoromethanesulfonate, tris (4-methoxyphenyl) sulfonium nonafluoro-n-butanesulfonate, tris (4-methoxyphenyl) sulfonium perfluoro-n-octanesulfonate, tris (4-methoxyphenyl) ) Sulfonium pyrenesulfonate, tris (4-methoxyphenyl) sulfonium n-dodecylbenzenesulfonate, tris (4-methoxyphenyl) sulfonium 4-toluenesulfonate, tris (4-methoxyphenyl) sulfoniumbenzenesulfonate, tris (4-methoxyphenyl) Sulfonium 10-camphor-sulfonate, tris (4-methoxyphenyl) sulfonium n-octanesulfonate, tris (4-methoxy Enyl) sulfonium 2-trifluoromethylbenzenesulfonate, tris (4-methoxyphenyl) sulfonium 4-trifluoromethylbenzenesulfonate, tris (4-methoxyphenyl) sulfonium perfluorobenzenesulfonate, bis (4-methoxyphenyl) 4-toluyl Sulfonium trifluoromethanesulfonate, bis (4-methoxyphenyl) 4-toluylsulfonium nonafluoro-n-butanesulfonate, bis (4-methoxyphenyl) 4-toluylsulfonium perfluoro-n-octanesulfonate, bis (4-methoxyphenyl) 4-toluylsulfonium pyrenesulfonate, bis (4-methoxyphenyl) 4-toluylsulfonium n-dodecylbenzenesulfonate, bis (4-meth Ciphenyl) 4-toluylsulfonium 4-toluenesulfonate, bis (4-methoxyphenyl) 4-toluylsulfonium benzenesulfonate, bis (4-methoxyphenyl) 4-toluylsulfonium 10-camphor-sulfonate, bis (4-methoxyphenyl) 4 -Toluylsulfonium n-octanesulfonate, bis (4-methoxyphenyl) 4-toluylsulfonium 2-trifluoromethylbenzenesulfonate, bis (4-methoxyphenyl) 4-toluylsulfonium 4-trifluoromethylbenzenesulfonate, bis (4- Methoxyphenyl) 4-toluylsulfonium perfluorobenzenesulfonate,

(4-fluorophenyl) diphenylsulfonium trifluoromethanesulfonate, (4-fluorophenyl) diphenylsulfonium nonafluoro-n-butanesulfonate, (4-fluorophenyl) diphenylsulfonium 10-camphor-sulfonate, tris (4-fluorophenyl) sulfonium Trifluoromethanesulfonate, tris (4-fluorophenyl) sulfonium nonafluoro-n-butanesulfonate, tris (4-fluorophenyl) sulfonium 10-camphor-sulfonate, tris (4-fluorophenyl) sulfonium 4-toluenesulfonate, 2,4 , 6-Trimethylphenyldiphenylsulfonium trifluoromethanesulfonate, 2,4,6-trimethylphenyldiphenylsulfoniu 2,4-difluorobenzenesulfonate, 2,4,6-trimethylphenyldiphenylsulfonium 4-toluenesulfonate, 2,4,6-trimethylphenyldiphenylsulfonium 4-trifluoromethylbenzenesulfonate, (4-t-butoxycarbonylmethoxyphenyl) ) Diphenyltrifluoromethanesulfonate, (4-t-butoxycarbonylmethoxyphenyl) diphenylnonafluoro-n-butanesulfonate, (4-t-butoxycarbonylmethoxyphenyl) diphenyl 4-trifluoromethylbenzenesulfonate, (4-t-butoxy) And carbonylmethoxyphenyl) diphenyl 2- (bicyclo [2.2.1] heptan-2-yl) -1,1,2,2-tetrafluoroethanesulfonate.

  Among these sulfonium salt compounds, triphenylsulfonium trifluoromethanesulfonate, (4-hydroxyphenyl) diphenylsulfonium trifluoromethanesulfonate, 2,4,6-trimethylphenyldiphenylsulfonium trifluoromethanesulfonate, 2,4,6-trimethylphenyldiphenyl Sulfonium 4-trifluoromethylbenzenesulfonate, (4-t-butoxycarbonylmethoxyphenyl) diphenyltrifluoromethanesulfonate, (4-t-butoxycarbonylmethoxyphenyl) diphenylnonafluoro-n-butanesulfonate, (4-t-butoxycarbonyl) Methoxyphenyl) diphenyl 4-trifluoromethylbenzenesulfonate, (4-t-butoxycarbonylmeth) Shifeniru) diphenyl 2- (bicyclo [2.2.1] heptan-2-yl) 1,1,2,2-tetrafluoroethane sulfonate is preferred because further improved line roughness characteristics.

  Examples of the iodonium salt compound include diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, diphenyliodonium pyrenesulfonate, diphenyliodonium n-dodecylbenzenesulfonate, diphenyliodonium 4- Toluene sulfonate, diphenyl iodonium benzene sulfonate, diphenyl iodonium 10-camphor sulfonate, diphenyl iodonium n-octane sulfonate, diphenyl iodonium 2-trifluoromethyl benzene sulfonate, diphenyl iodonium 4-trifluoromethyl benzene sulfonate, diphenyl iodonium perfluoro Nzensulfonate, di (4-toluyl) iodonium trifluoromethanesulfonate, di (4-toluyl) iodonium nonafluoro-n-butanesulfonate, di (4-toluyl) iodonium perfluoro-n-octanesulfonate, di (4-toluyl) Iodonium pyrenesulfonate, di (4-toluyl) iodonium n-dodecylbenzenesulfonate, di (4-toluyl) iodonium 4-toluenesulfonate, di (4-toluyl) iodoniumbenzenesulfonate, di (4-toluyl) iodonium 10-camphor Sulfonate, di (4-toluyl) iodonium n-octane sulfonate, di (4-toluyl) iodonium 2-trifluoromethylbenzenesulfonate, di (4-toluyl) iodonium 4 Trifluoromethylbenzene sulfonate, di (4-toluyl) iodonium perfluoro sulfonate,

Bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) iodonium perfluoro-n-octanesulfonate, Bis (4-t-butylphenyl) iodonium pyrenesulfonate, bis (4-t-butylphenyl) iodonium n-dodecylbenzenesulfonate, bis (4-t-butylphenyl) iodonium 4-toluenesulfonate, bis (4-t- Butylphenyl) iodoniumbenzenesulfonate, bis (4-t-butylphenyl) iodonium 10-camphor-sulfonate, bis (4-t-butylphenyl) iodonium n-octanesulfonate, bis (4-t-butyl) Enyl) iodonium 2-trifluoromethylbenzenesulfonate, bis (4-tert-butylphenyl) iodonium 4-trifluoromethylbenzenesulfonate, bis (4-tert-butylphenyl) iodonium perfluorobenzenesulfonate, bis (4-t- Butylphenyl) iodonium 2,4-difluorobenzenesulfonate, bis (3,4-dimethylphenyl) iodonium trifluoromethanesulfonate, bis (3,4-dimethylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (3,4 Dimethylphenyl) iodonium perfluoro-n-octanesulfonate, bis (3,4-dimethylphenyl) iodonium pyrenesulfonate, bis (3,4-dimethylphenyl) iodonium n-do Silbenzene sulfonate, bis (3,4-dimethylphenyl) iodonium 4-toluenesulfonate, bis (3,4-dimethylphenyl) iodonium benzene sulfonate, bis (3,4-dimethylphenyl) iodonium 10-camphor-sulfonate, bis ( 3,4-dimethylphenyl) iodonium n-octanesulfonate, bis (3,4-dimethylphenyl) iodonium 2-trifluoromethylbenzenesulfonate, bis (3,4-dimethylphenyl) iodonium 4-trifluoromethylbenzenesulfonate, bis (3,4-dimethylphenyl) iodonium perfluorobenzenesulfonate,

(4-nitrophenyl) phenyliodonium trifluoromethanesulfonate, (4-nitrophenyl) phenyliodonium nonafluoro-n-butanesulfonate, (4-nitrophenyl) phenyliodonium perfluoro-n-octanesulfonate, (4-nitrophenyl) Phenyliodonium pyrenesulfonate, (4-nitrophenyl) phenyliodonium n-dodecylbenzenesulfonate, (4-nitrophenyl) phenyliodonium 4-toluenesulfonate, (4-nitrophenyl) phenyliodoniumbenzenesulfonate, (4-nitrophenyl) phenyl Iodonium 10-camphor-sulfonate, (4-nitrophenyl) phenyliodonium n-octanesulfonate, (4-nitrophenyl) Phenyliodonium 2-trifluoromethylbenzenesulfonate, (4-nitrophenyl) phenyliodonium 4-trifluoromethylbenzenesulfonate, (4-nitrophenyl) phenyliodonium perfluorobenzenesulfonate, bis (3-nitrophenyl) iodonium trifluoromethanesulfonate Bis (3-nitrophenyl) iodonium nonafluoro-n-butanesulfonate, bis (3-nitrophenyl) iodonium perfluoro-n-octanesulfonate, bis (3-nitrophenyl) iodonium pyrenesulfonate, bis (3-nitrophenyl) ) Iodonium n-dodecylbenzenesulfonate, bis (3-nitrophenyl) iodonium 4-toluenesulfonate, bis (3-nitrofe) L) iodonium benzenesulfonate, bis (3-nitrophenyl) iodonium 10-camphor-sulfonate, bis (3-nitrophenyl) iodonium n-octanesulfonate, bis (3-nitrophenyl) iodonium 2-trifluoromethylbenzenesulfonate, bis (3-nitrophenyl) iodonium 4-trifluoromethylbenzenesulfonate, bis (3-nitrophenyl) iodonium perfluorobenzenesulfonate,

(4-methoxyphenyl) phenyliodonium trifluoromethanesulfonate, (4-methoxyphenyl) phenyliodonium nonafluoro-n-butanesulfonate, (4-methoxyphenyl) phenyliodonium perfluoro-n-octanesulfonate, (4-methoxyphenyl) Phenyliodonium pyrenesulfonate, (4-methoxyphenyl) phenyliodonium n-dodecylbenzenesulfonate, (4-methoxyphenyl) phenyliodonium 4-toluenesulfonate, (4-methoxyphenyl) phenyliodoniumbenzenesulfonate, (4-methoxyphenyl) phenyl Iodonium 10-camphor-sulfonate, (4-methoxyphenyl) phenyliodonium n-octanesulfonate, ( -Methoxyphenyl) phenyliodonium 2-trifluoromethylbenzenesulfonate, (4-methoxyphenyl) phenyliodonium 4-trifluoromethylbenzenesulfonate, (4-methoxyphenyl) phenyliodonium perfluorobenzenesulfonate, (4-fluorophenyl) phenyl Iodonium trifluoromethanesulfonate, (4-fluorophenyl) phenyliodonium nonafluoro-n-butanesulfonate, (4-fluorophenyl) phenyliodonium 10-camphor-sulfonate, bis (4-fluorophenyl) iodonium trifluoromethanesulfonate, bis (4 -Fluorophenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-fluorophenyl) iodine Nium 10-camphor-sulfonate, bis (4-chlorophenyl) iodonium trifluoromethanesulfonate, bis (4-chlorophenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-chlorophenyl) iodonium perfluoro-n-octanesulfonate, bis ( 4-chlorophenyl) iodonium pyrenesulfonate, bis (4-chlorophenyl) iodonium n-dodecylbenzenesulfonate, bis (4-chlorophenyl) iodonium 4-toluenesulfonate, bis (4-chlorophenyl) iodoniumbenzenesulfonate, bis (4-chlorophenyl) iodonium 10-camphor-sulfonate, bis (4-chlorophenyl) iodonium n-octanesulfonate, bis (4-chlorophene) Nyl) iodonium 2-trifluoromethylbenzenesulfonate, bis (4-chlorophenyl) iodonium 4-trifluoromethylbenzenesulfonate, bis (4-chlorophenyl) iodonium perfluorobenzenesulfonate,

Bis (4-trifluoromethylphenyl) iodonium trifluoromethanesulfonate, bis (4-trifluoromethylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-trifluoromethylphenyl) iodonium perfluoro-n-octanesulfonate, Bis (4-trifluoromethylphenyl) iodonium pyrenesulfonate, bis (4-trifluoromethylphenyl) iodonium n-dodecylbenzenesulfonate, bis (4-trifluoromethylphenyl) iodonium 4-toluenesulfonate, bis (4-trifluoro Methylphenyl) iodonium benzenesulfonate, bis (4-trifluoromethylphenyl) iodonium 10-camphor-sulfonate, bis (4-trifluoromethyl) Ruphenyl) iodonium n-octanesulfonate, bis (4-trifluoromethylphenyl) iodonium 2-trifluoromethylbenzenesulfonate, bis (4-trifluoromethylphenyl) iodonium 4-trifluoromethylbenzenesulfonate, bis (4-trifluoro Methylphenyl) iodonium perfluorobenzenesulfonate, di (1-naphthyl) iodonium trifluoromethanesulfonate, di (1-naphthyl) iodonium nonafluoro-n-butanesulfonate, di (1-naphthyl) iodonium perfluoro-n-octanesulfonate, Di (1-naphthyl) iodonium pyrenesulfonate, di (1-naphthyl) iodonium n-dodecylbenzenesulfonate, di (1-naphthyl) iodonium 4-toluenesulfonate, di (1-naphthyl) iodonium benzenesulfonate, di (1-naphthyl) iodonium 10-camphor-sulfonate, di (1-naphthyl) iodonium n-octanesulfonate, di (1-naphthyl) iodonium 2-tri Examples thereof include fluoromethylbenzene sulfonate, di (1-naphthyl) iodonium 4-trifluoromethylbenzene sulfonate, and di (1-naphthyl) iodonium perfluorobenzene sulfonate.

  Of these iodonium salt compounds, diphenyliodonium trifluoromethanesulfonate is preferable because it improves the line roughness characteristics.

  As said diazonium salt compound, the disulfonyl diazomethane compound represented by following formula (5) can be mentioned, for example.

（式（５）において、各Ｒ¹⁰は相互に独立にアルキル基、アリール基、ハロゲン置換アルキル基、ハロゲン置換アリール基等の１価の基を表す）

(In Formula (5), each R ¹⁰ independently represents a monovalent group such as an alkyl group, an aryl group, a halogen-substituted alkyl group, or a halogen-substituted aryl group)

Specific examples of the disulfonyldiazomethane compound include bis (trifluoromethanesulfonyl) diazomethane, bis (cyclohexanesulfonyl) diazomethane, bis (phenylsulfonyl) diazomethane, bis (4-toluenesulfonyl) diazomethane, and bis (2,4-dimethylbenzenesulfonyl). ) Diazomethane, bis (4-t-butylphenylsulfonyl) diazomethane, bis (4-chlorobenzenesulfonyl) diazomethane, methylsulfonyl, 4-toluenesulfonyldiazomethane, cyclohexanesulfonyl, 4-toluenesulfonyldiazomethane, cyclohexanesulfonyl, 1,1-dimethyl Ethanesulfonyldiazomethane, bis (1,1-dimethylethanesulfonyl) diazomethane, bis (1-methylethanesulfonyl) di Zomethane, bis (3,3-dimethyl-1,5-dioxaspiro [5.5] dodecane-8-sulfonyl) diazomethane, bis (1,4-dioxaspiro [4.5] decan-7-sulfonyl) diazomethane, bis ( t-butylsulfonyl) diazomethane and the like.
Among these, bis (1,4-dioxaspiro [4.5] decane-7-sulfonyl) diazomethane is preferable because it further improves the line roughness characteristics.

As an acid generator, compounds that can be preferably used in addition to at least one compound selected from the sulfonyloxyimide compounds, sulfonium salt compounds, iodonium salt compounds, and diazonium salt compounds include disulfonylmethane compounds, oxime sulfonate compounds, hydrazine sulfonates. A compound can be mentioned.
As a disulfonylmethane compound, the compound represented by following formula (6) can be mentioned, for example.

〔式（６）において、各Ｒ¹¹は相互に独立に直鎖状もしくは分岐状の１価の脂肪族炭化水素基、シクロアルキル基、アリール基、アラルキル基またはヘテロ原子を有する他の１価の有機基を示し、ＶおよびＷは相互に独立に、アリール基、水素原子、直鎖状もしくは分岐状の１価の脂肪族炭化水素基またはヘテロ原子を有する他の１価の有機基を表し、かつＶおよびＷの少なくとも一方がアリール基であるか、あるいはＶとＷが相互に連結して少なくとも１個の不飽和結合を有する炭素単環構造または炭素多環構造を形成しているか、あるいはＶとＷが相互に連結して下記式

（但し、Ｖ’およびＷ’は相互に独立に、かつ複数存在するＶ’およびＷ’はそれぞれ同一でも異なってもよく、水素原子、ハロゲン原子、直鎖状もしくは分岐状のアルキル基、シクロアルキル基、アリール基またはアラルキル基を表すか、あるいは同一のもしくは異なる炭素原子に結合したＶ’とＷ’が相互に連結して炭素単環構造を形成しており、ｒは２〜１０の整数である）で表される基を形成している。〕

[In Formula (6), each R ¹¹ is independently a linear or branched monovalent aliphatic hydrocarbon group, a cycloalkyl group, an aryl group, an aralkyl group, or another monovalent having a hetero atom. Represents an organic group, and V and W each independently represent an aryl group, a hydrogen atom, a linear or branched monovalent aliphatic hydrocarbon group or another monovalent organic group having a hetero atom, And at least one of V and W is an aryl group, or V and W are connected to each other to form a carbon monocyclic structure or a carbon polycyclic structure having at least one unsaturated bond, or V And W are connected to each other

(However, V ′ and W ′ are independent of each other, and a plurality of V ′ and W ′ may be the same or different and each represents a hydrogen atom, a halogen atom, a linear or branched alkyl group, cycloalkyl A group, an aryl group or an aralkyl group, or V ′ and W ′ bonded to the same or different carbon atoms are connected to each other to form a carbon monocyclic structure, and r is an integer of 2 to 10 A group represented by (A). ]

  Moreover, as said oxime sulfonate compound, the compound represented by following formula (7-1) or (7-2) can be mentioned, for example.

（式（７−１）および式（７−２）において、Ｒ¹²およびＲ¹³は相互に独立に１価の有機基を表す）

(In Formula (7-1) and Formula (7-2), R ¹² and R ¹³ each independently represent a monovalent organic group)

In formula (7-1) and formula (7-2), preferred specific examples of R ¹² are methyl group, ethyl group, n-propyl group, phenyl group, tosyl group, trifluoromethyl group, pentafluoroethyl group. Moreover, as a preferable specific example of R < ¹³ >, a phenyl group, a tosyl group, 1-naphthyl group, etc. can be mentioned.

Specific examples of the hydrazine sulfonate compound include bis (benzenesulfonyl) hydrazine, bis (4-toluenesulfonyl) hydrazine, bis (trifluoromethanesulfonyl) hydrazine, bis (pentafluoroethanesulfonyl) hydrazine, and bis (n-propanesulfonyl). Examples include hydrazine, benzenesulfonyl hydrazine, 4-toluenesulfonyl hydrazine, trifluoromethanesulfonyl hydrazine, pentafluoroethanesulfonyl hydrazine, n-propanesulfonyl hydrazine, trifluoromethanesulfonyl, 4-toluenesulfonyl hydrazine, and the like.
These other acid generators can be used alone or in admixture of two or more.

  In the present invention, the amount of the acid generator (A) used is preferably 20 to 80 parts by weight, more preferably 20 to 40 parts by weight per 100 parts by weight of the acid dissociable group-containing resin (B) described later. . In this case, if the amount of the acid generator (A) used is less than 20 parts by weight, the resolution tends to decrease. On the other hand, if it exceeds 80 parts by weight, the resist coating property, the adhesion of the resist pattern to the substrate, the pattern There exists a tendency for a shape, heat resistance, etc. to fall.

Acid-dissociable group-containing resin (B)
The component (B) in the present invention is an alkali-insoluble or hardly alkali-soluble resin having an acid-dissociable group, and is made of a resin that becomes readily alkali-soluble when the acid-dissociable group is dissociated.
The term “alkali-insoluble or alkali-insoluble” as used herein is employed when a resist pattern is formed from a resist film formed using a radiation-sensitive resin composition containing an acid-dissociable group-containing resin (B). When developing a film using only the acid-dissociable group-containing resin (B) instead of the resist film under alkaline development conditions, 50% or more of the initial film thickness of the film remains after development. means.

As the acid dissociable group-containing resin (B), for example, a hydrogen atom of the acidic functional group in an alkali-soluble resin having one or more acidic functional groups such as a phenolic hydroxyl group and a carboxyl group can be used in the presence of an acid tail. Examples of the resin substituted with one or more acid-dissociable groups that can be dissociated include alkali-insoluble or hardly alkali-soluble resins.
In the present invention, preferred acid dissociable group-containing resins (B) include, for example, a repeating unit represented by the following formula (1) (hereinafter referred to as “repeating unit (1)”) and a following formula (2). And a resin containing a repeating unit represented by the following formula (3) and / or a repeating unit represented by the following formula (3) (hereinafter referred to as “repeat unit (3)”). it can.

（式（１）において、Ｒ¹は水素原子またはメチル基を表し、Ｒ²は１価の有機基（但し、式（２）における−ＯＲ⁵に相当する基を除く）を表し、ｔは０〜３の整数であり、ｓは１〜３の整数であり、複数存在するＲ²は相互に同一でも異なってもよい。
式（２）において、Ｒ³は水素原子またはメチル基を表し、Ｒ⁴は１価の有機基（但し、−ＯＲ⁵に相当する基を除く）を表し、Ｒ⁵は１価の酸解離性基を表し、ｑは０〜３の整数であり、ｐは１〜３の整数であり、複数存在するＲ⁴およびＲ⁵はそれぞれ相互に同一でも異なってもよい。
式（３）において、Ｒ⁶は水素原子またはメチル基を表し、Ｒ⁷はｔ−ブチル基、１−メチルシクロペンチル基または１−エチルシクロペンチル基、２−メチル−２−アダマンチル基、２−エチル−２−アダマンチル基を表す。

(In Formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a monovalent organic group (excluding the group corresponding to —OR ⁵ in Formula (2)), and t is 0 an -3 integer, s is an integer from 1 to 3, R ² existing in plural numbers may be the same or different from each other.
In the formula (2), R ³ represents a hydrogen atom or a methyl group, R ⁴ represents a monovalent organic group (excluding a group corresponding to —OR ⁵ ), and R ⁵ represents a monovalent acid dissociability. Represents a group, q is an integer of 0 to 3, p is an integer of 1 to 3, and a plurality of R ⁴ and R ⁵ may be the same or different from each other.
In the formula (3), R ⁶ represents a hydrogen atom or a methyl group, and R ⁷ represents a t-butyl group, a 1-methylcyclopentyl group or a 1-ethylcyclopentyl group, a 2-methyl-2-adamantyl group, 2-ethyl- Represents a 2-adamantyl group.

Examples of the monovalent organic group represented by R ² in Formula (1) and R ⁴ in Formula (2) include, for example, a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, and 6 to 20 carbon atoms. A monovalent aromatic hydrocarbon group, a monovalent oxygen atom-containing organic group, a monovalent nitrogen atom-containing organic group and the like can be mentioned.
Examples of the alkyl group include methyl, ethyl, n-propyl, i-propyl, n-butyl, 2-methylpropyl, 1-methylpropyl, t-butyl, cyclopentyl, and cyclohexyl. Groups and the like.
Examples of the monovalent aromatic hydrocarbon group include a phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 2,4-xylyl group, 2,6-xylyl group, 3,5- A xylyl group, a mesityl group, an o-cumenyl group, an m-cumenyl group, a p-cumenyl group, a benzyl group, a phenethyl group, a 1-naphthyl group, a 2-naphthyl group, and the like can be given.

  Examples of the monovalent oxygen atom-containing organic group include, for example, carboxyl group; hydroxymethyl group, 1-hydroxyethyl group, 2-hydroxyethyl group, 1-hydroxypropyl group, 2-hydroxypropyl group, 3-hydroxypropyl group. 1-hydroxybutyl group, 2-hydroxybutyl group, 3-hydroxybutyl group, 4-hydroxybutyl group, 3-hydroxycyclopentyl group, 4-hydroxycyclohexyl group, etc. Or a cyclic hydroxyalkyl group; methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, 2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group, cyclopentyloxy group, cyclohexyl C1-C8 straight, branched or cyclic such as oxy group A linear alkoxycarbonyloxy group having 2 to 9 carbon atoms such as a methoxycarbonyloxy group, an ethoxycarbonyloxy group, an n-propoxycarbonyloxy group, and an n-butoxycarbonyloxy group; (1-methoxyethoxy) methyl Group, (1-ethoxyethoxy) methyl group, (1-n-propoxyethoxy) methyl group, (1-n-butoxyethoxy) methyl group, (1-cyclopentyloxyethoxy) methyl group, (1-cyclohexyloxyethoxy) A linear, branched or cyclic (1-alkoxyalkoxy) alkyl group having 3 to 11 carbon atoms such as a methyl group, a (1-methoxypropoxy) methyl group, a (1-ethoxypropoxy) methyl group and an ethoxyethyl group; Methoxycarbonyloxymethyl group, ethoxycarbonyloxyme Group, n-propoxycarbonyloxymethyl group, i-propoxycarbonyloxymethyl group, n-butoxycarbonyloxymethyl group, t-butoxycarbonyloxymethyl group, cyclopentyloxycarbonyloxymethyl group, cyclohexyloxycarbonyloxymethyl group, etc. Examples thereof include a linear, branched or cyclic alkoxycarbonyloxyalkyl group having 3 to 10 carbon atoms.

  Examples of the monovalent nitrogen atom-containing organic group include cyano group; cyanomethyl group, 1-cyanoethyl group, 2-cyanoethyl group, 1-cyanopropyl group, 2-cyanopropyl group, 3-cyanopropyl group, 1- C2-C9 linear, branched or cyclic cyanoalkyl groups such as cyanobutyl group, 2-cyanobutyl group, 3-cyanobutyl group, 4-cyanobutyl group, 3-cyanocyclopentyl group, 4-cyanocyclohexyl group, etc. Can be mentioned.

In the formula (2), examples of the monovalent acid dissociable group for R ⁵ include a substituted methyl group, a 1-substituted ethyl group, a 1-branched alkyl group, a triorganosilyl group, a triorganogermyl group, and an alkoxycarbonyl group. An acyl group, a monovalent cyclic acid dissociable group, and the like.
Examples of the substituted methyl group include a methoxymethyl group, a methylthiomethyl group, an ethoxymethyl group, an ethylthiomethyl group, a methoxyethoxymethyl group, a benzyloxymethyl group, a benzylthiomethyl group, a phenacyl group, a bromophenacyl group, and a methoxyphenacyl group. Group, methylthiophenacyl group, α-methylphenacyl group, cyclopropylmethyl group, benzyl group, diphenylmethyl group, triphenylmethyl group, bromobenzyl group, nitrobenzyl group, methoxybenzyl group, methylthiobenzyl group, ethoxybenzyl group , Ethylthiobenzyl group, piperonyl group, methoxycarbonylmethyl group, ethoxycarbonylmethyl group, n-propoxycarbonylmethyl group, i-propoxycarbonylmethyl group, n-butoxycarbonylmethyl group, t-butoxy Rubonirumechiru group, and the like can be mentioned.

Examples of the 1-substituted ethyl group include 1-methoxyethyl group, 1-methylthioethyl group, 1,1-dimethoxyethyl group, 1-ethoxyethyl group, 1-ethylthioethyl group, 1,1-diethoxy. Ethyl group, 1-ethoxypropyl group, 1-propoxyethyl group, 1-cyclohexyloxyethyl group, 1-phenoxyethyl group, 1-phenylthioethyl group, 1,1-diphenoxyethyl group, 1-benzyloxyethyl group 1-benzylthioethyl group, 1-cyclopropylethyl group, 1-phenylethyl group, 1,1-diphenylethyl group, 1-methoxycarbonylethyl group, 1-ethoxycarbonylethyl group, 1-n-propoxycarbonylethyl Group, 1-isopropoxycarbonylethyl group, 1-n-butoxycarbonylethyl group, 1-t-butyl group Butoxycarbonyl ethyl group and the like.
Examples of the 1-branched alkyl group include i-propyl group, sec-butyl group, t-butyl group, 1,1-dimethylpropyl group, 1-methylbutyl group, 1,1-dimethylbutyl group and the like. Can do.

Examples of the triorganosilyl group include trimethylsilyl group, ethyldimethylsilyl group, methyldiethylsilyl group, triethylsilyl group, i-propyldimethylsilyl group, methyldi-i-propylsilyl group, tri-i-propylsilyl group, Examples thereof include a t-butyldimethylsilyl group, a methyldi-t-butylsilyl group, a tri-t-butylsilyl group, a phenyldimethylsilyl group, a methyldiphenylsilyl group, and a triphenylsilyl group.
Examples of the triorganogermyl group include trimethylgermyl group, ethyldimethylgermyl group, methyldiethylgermyl group, triethylgermyl group, isopropyldimethylgermyl group, methyldi-i-propylgermyl group, and tri-i. -Propylgermyl group, t-butyldimethylgermyl group, methyldi-t-butylgermyl group, tri-t-butylgermyl group, phenyldimethylgermyl group, methyldiphenylgermyl group, triphenylgermyl group, etc. it can.

As said alkoxycarbonyl group, a methoxycarbonyl group, an ethoxycarbonyl group, i-propoxycarbonyl group, t-butoxycarbonyl group etc. can be mentioned, for example.
Examples of the acyl group include acetyl group, propionyl group, butyryl group, heptanoyl group, hexanoyl group, valeryl group, pivaloyl group, isovaleryl group, lauroyl group, myristoyl group, palmitoyl group, stearoyl group, oxalyl group, malonyl group, Succinyl group, glutaryl group, adipoyl group, piperoyl group, suberoyl group, azelaoil group, sebacoyl group, acryloyl group, propioroyl group, methacryloyl group, crotonoyl group, oleoyl group, maleoyl group, fumaroyl group, mesaconoyl group, canphoroyl group, benzoyl Group, phthaloyl group, isophthaloyl group, terephthaloyl group, naphthoyl group, toluoyl group, hydroatropoyl group, atropoyl group, cinnamoyl group, furoyl group, thenoyl group, nicotinoyl group, isoni Chinoiru group, 4-toluenesulfonyl group, and mesyl group.

  Furthermore, examples of the monovalent cyclic acid dissociable group include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cyclohexenyl group, a 4-methoxycyclohexyl group, a tetrahydrofuranyl group, a tetrahydropyranyl group, and a tetrahydrothiofuranyl group. Group, tetrahydrothiopyranyl group, 3-bromotetrahydropyranyl group, 4-methoxytetrahydropyranyl group, 4-methoxytetrahydrothiopyranyl group, 3-tetrahydrothiophene-1,1-dioxide group and the like. .

Preferred repeating units (1) in the present invention include, for example, 2-hydroxystyrene, 3-hydroxystyrene, 4-hydroxystyrene, 2-hydroxy-α-methylstyrene, 3-hydroxy-α-methylstyrene, 4-hydroxy -Α-methylstyrene, 2-methyl-3-hydroxystyrene, 4-methyl-3-hydroxystyrene, 5-methyl-3-hydroxystyrene, 2-methyl-4-hydroxystyrene, 3-methyl-4-hydroxystyrene , 3,4-dihydroxystyrene, 2,4,6-trihydroxystyrene and the like, which are repeating units having a polymerizable unsaturated bond cleaved.
In the resin (B), the repeating unit (1) may be present alone or in combination of two or more.

In addition, preferred repeating units (2) in the present invention include, for example, 4-t-butoxystyrene, 4-t-butoxy-α-methylstyrene, 4- (2-ethyl-2-propoxy) styrene, 4- ( 2-ethyl-2-propoxy) -α-methylstyrene, 4- (1-ethoxyethoxy) styrene, 4- (1-ethoxyethoxy) -α-methylstyrene, etc. Can be mentioned.
In the resin (B), the repeating unit (2) may be used alone or in combination of two or more.

In addition, as the repeating unit (3) in the present invention, t-butyl (meth) acrylate, 1-methylcyclopentyl (meth) acrylate and 1-ethylcyclopentyl (meth) acrylate, 2-methyl (meth) acrylate And a repeating unit in which a polymerizable unsaturated bond such as -2-adamantyl is cleaved.
In the resin (B), the repeating unit (3) may be used alone or in combination of two or more.

In the present invention, the resin (B) may further have a repeating unit other than the repeating unit (1) to the repeating unit (3) (hereinafter referred to as “other repeating unit”).
As other repeating units, for example, styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-methoxystyrene, 3-methoxystyrene, 4-methoxystyrene, 4- (2 Vinyl aromatic compounds such as -t-butoxycarbonylethyloxy) styrene; methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, (meth ) N-butyl acrylate, 2-methylpropyl (meth) acrylate, 1-methylpropyl (meth) acrylate, n-pentyl (meth) acrylate, neopentyl (meth) acrylate, n- (meth) acrylate Hexyl, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, ( T) 2-hydroxy-n-propyl acrylate, 3-hydroxy-n-propyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, 1-methyladamantyl (meth) acrylate, 1-ethyladamantyl methacrylate), 8-methyl-8-tricyclodecyl (meth) acrylate, 8-ethyl-8-tricyclodecyl (meth) acrylate, 3-methyl-3- (meth) acrylate (Meth) acrylic acid esters such as tetracyclododecenyl, 3-ethyl-3-tetracyclododecenyl (meth) acrylate, and 2,5-dimethylhexane-2,5-di (meth) acrylate ;

Unsaturated carboxylic acids (anhydrides) such as (meth) acrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, cinnamic acid; 2-carboxyethyl (meth) acrylate, (meth) acrylic acid 2 -Carboxyalkyl esters of unsaturated carboxylic acids such as carboxy-n-propyl and (meth) acrylic acid 3-carboxy-n-propyl; (meth) acrylonitrile, α-chloroacrylonitrile, crotonnitrile, maleinonitrile, fumaronitrile, etc. Unsaturated nitrile compounds; unsaturated amide compounds such as (meth) acrylamide, N, N-dimethyl (meth) acrylamide, crotonamide, maleamide and fumaramide; unsaturated imides such as maleimide, N-phenylmaleimide and N-cyclohexylmaleimide Compound; N-vinyl-ε-cap Units in which a polymerizable unsaturated bond such as loractam, N-vinylpyrrolidone, 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-vinylimidazole, 4-vinylimidazole, or other nitrogen-containing vinyl compounds is cleaved Can be mentioned.
In the resin (B), other repeating units may be used alone or in combination of two or more.

  Particularly preferred resins (B) in the present invention include, for example, 4-hydroxystyrene / 4-t-butoxystyrene copolymer, 4-hydroxystyrene / 4-t-butoxystyrene / acrylic acid 1-methylcyclopentyl copolymer. 4-hydroxystyrene / 4-t-butoxystyrene / 1-ethylcyclopentyl acrylate copolymer, 4-hydroxystyrene / 4-t-butoxystyrene / styrene copolymer, 4-hydroxystyrene / t-butyl acrylate / Styrene copolymer, 4-hydroxystyrene / 1-methylcyclopentyl acrylate / styrene copolymer, 4-hydroxystyrene / 1-ethylcyclopentyl acrylate / styrene copolymer, 4-hydroxystyrene / 4-t-butoxy Styrene / 2,5-dimethylhexane-2 5-diacrylate copolymer, may be mentioned 4-hydroxystyrene / acrylic acid 2-methyl-2-adamantyl copolymers.

  In the acid dissociable group-containing resin (B), the acid dissociable group introduction rate (acid dissociation property relative to the total number of unprotected acidic functional groups and acid dissociable groups in the acid dissociable group-containing resin (B)) The ratio of the number of groups) cannot be defined unconditionally depending on the type of acid-dissociable group or the alkali-soluble resin into which the group is introduced, but is preferably 10 to 100%, more preferably 15 to 100%.

  In the resin (B), the content of the repeating unit (1) is 55 to 85 mol%, preferably 65 to 75 mol%, and the content of the repeating unit (2) is 10 to 40 mol%, preferably 20 to 35 mol%, the content of the repeating unit (3) is 5 to 35 mol%, preferably 10 to 35 mol%, and the content of the other repeating units is usually 25 mol% or less, Preferably it is 10 mol% or less. In this case, if the content of the repeating unit (1) is less than 60 mol%, the adhesion of the resist pattern to the substrate tends to be reduced, whereas if it exceeds 85 mol%, the contrast after development tends to be reduced. is there. In addition, when the content of the repeating unit (2) is less than 10 mol%, the resolution tends to decrease, and when it exceeds 40 mol%, the adhesion of the resist pattern to the substrate tends to decrease. In addition, when the content of the repeating unit (3) is less than 5 mol%, the resolution tends to decrease. On the other hand, when the content exceeds 35 mol%, the dry etching resistance may be insufficient. Furthermore, when other repeating units exceed 25 mol%, the resolution tends to decrease.

The polystyrene-reduced weight molecular weight (hereinafter referred to as “Mw”) of the acid-dissociable group-containing resin (B) measured by gel permeation chromatography (GPC) is preferably 1,000 to 150,000, more preferably 3,000. ˜100,000, more preferably 5,000 to 30,000.
Moreover, the ratio (Mw / Mn) of Mw of the acid dissociable group-containing resin (B) and polystyrene-equivalent molecular weight (hereinafter referred to as “Mn”) measured by gel permeation chromatography (GPC) is usually 1 -10, preferably 1-5.
In this invention, acid dissociable group containing resin (B) can be used individually or in mixture of 2 or more types.

Other Components Alkali Dissolution Control Agent In the positive radiation sensitive resin composition of the present invention, the following alkali dissolution control agent can be blended in some cases.
Examples of the alkali dissolution control agent include compounds in which a hydrogen atom of an acidic functional group such as a phenolic hydroxyl group or a carboxyl group is substituted with an acid dissociable group or a t-butoxycarbonylmethyl group.
Examples of the acid dissociable group include a substituted methyl group, a 1-substituted ethyl group, a 1-substituted-n-propyl group, a 1-branched alkyl group exemplified for the acid dissociable group in the acid dissociable group-containing resin, Examples thereof include the same groups as silyl group, germyl group, alkoxycarbonyl group, acyl group, cyclic acid dissociable group and the like.

Examples of the alkali dissolution inhibitor in the positive radiation sensitive resin composition of the present invention include steroids (bile acids) such as cholic acid, deoxycholic acid, and lithocholic acid, and fats such as adamantane carboxylic acid and adamantane dicarboxylic acid. A compound in which a hydrogen atom of a carboxyl group in a carboxylic acid compound having a cyclic ring or an aromatic ring is substituted with the acid dissociable group or t-butoxycarbonylmethyl group is preferable.
The blending amount of the alkali solubility control agent in the positive radiation sensitive resin composition is 0.5 to 50 parts by weight, preferably 1 to 30 parts by weight, more preferably 2 to 2 parts by weight based on 100 parts by weight of the acid dissociable resin. 20 parts by weight. Moreover, an alkali solubility control agent can be used individually or in mixture of 2 or more types.

The acid diffusion control agent, the alkali-soluble resin for acid dissociable resin, the surfactant, the sensitizer, and the solvent, which are other components blended in the radiation sensitive resin composition, will be described.
Acid Diffusion Control Agent The radiation sensitive resin composition controls the diffusion phenomenon in the resist film of the acid generated from the acid generator by EB, X-ray or EUV irradiation, and undesired chemical reaction in the non-irradiated region. It is preferable to add an acid diffusion controller having an inhibitory action.
By using such an acid diffusion control agent, the storage stability of the composition is improved, the resolution is improved as a resist, and due to fluctuations in the holding time (PED) from irradiation to heat treatment after irradiation. Changes in the line width of the resist pattern can be suppressed, and the process stability is extremely excellent.

式（８）において、各Ｒ¹⁴は相互に独立に水素原子、アルキル基、アリール基またはアラルキル基を示し、これらの基は例えばヒドロキシ基等の官能基で置換されていてもよい。 As the acid diffusion controller, a nitrogen-containing organic compound whose basicity is not changed by radiation irradiation or heat treatment in the resist pattern forming step is preferable.
As such a nitrogen-containing organic compound, for example, a compound represented by the following formula (8) (hereinafter referred to as “nitrogen-containing compound (α))”, a diamino compound having two nitrogen atoms in the same molecule ( Hereinafter, referred to as “nitrogen-containing compound (β)”), diamino polymer having 3 or more nitrogen atoms (hereinafter referred to as “nitrogen-containing compound (γ)”), amide group-containing compound, urea compound, nitrogen-containing complex. A ring compound etc. are mentioned.

In the formula (8), each R ¹⁴ independently represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and these groups may be substituted with a functional group such as a hydroxy group.

Examples of the nitrogen-containing compound (α) include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; di-n-butylamine, di-n- Dialkylamines such as pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine; triethylamine, tri-n-propylamine, Trialkylamines such as tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine Aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methyl Ruanirin, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, aromatic amines such as 1-naphthylamine, and the like.
Examples of the nitrogen-containing compound (β) include ethylenediamine, N, N, N ′,
N′-tetramethylethylenediamine, N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, 4,4′-diaminodiphenylamine, 2,2′-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 2 -(4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,4-bis [1- (4-aminophenyl) ) -1-Methylethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl Benzene, and the like.
Examples of the nitrogen-containing compound (γ) include polymers of polyethyleneimine, polyallylamine, dimethylaminoethylacrylamide, and the like.
Examples of the amide group-containing compound include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone and the like. Is mentioned.
Examples of the urea compound include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tributylthiourea and the like. It is done.

Examples of the nitrogen-containing heterocyclic compound include imidazoles such as imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, 2-phenylbenzimidazole; pyridine, 2-methylpyridine, 4-methyl. Such as pyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, N-methyl-4-phenylpyridine, nicotine, nicotinic acid, nicotinamide, quinoline, 8-oxyquinoline, acridine, etc. In addition to pyridines, pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, morpholine, 4-methylmorpholine, piperazine, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2.2.2] octane, phenanthro Emissions, and the like.
Moreover, the nitrogen-containing compound which has an acid dissociable group can also be used as said nitrogen-containing organic compound.
Examples of the nitrogen-containing compound having an acid dissociable group include N- (t-butoxycarbonyl) piperidine, N- (t-butoxycarbonyl) imidazole, N- (t-butoxycarbonyl) benzimidazole, N- (t -Butoxycarbonyl) 2-phenylbenzimidazole, N- (t-butoxycarbonyl) dioctylamine, N- (t-butoxycarbonyl) diethanolamine, N- (t-butoxycarbonyl) dicyclohexylamine, N- (t-butoxycarbonyl) diphenylamine Etc.

Of these nitrogen-containing organic compounds, nitrogen-containing compounds (α), nitrogen-containing compounds (β), nitrogen-containing heterocyclic compounds, nitrogen-containing compounds having an acid-dissociable group, and the like are preferable.
The acid diffusion control agents can be used alone or in admixture of two or more.
The compounding amount of the acid diffusion controller is preferably 0.1 to 1 part by weight, more preferably 0.2 to 100 parts by weight per 100 parts by weight of the alkali-soluble resin in the acid-dissociable group-containing resin in the positive radiation-sensitive resin composition. 0.8 parts by weight. In this case, when the compounding amount of the acid diffusion controller exceeds 1 part by weight, the sensitivity as a resist and the developability of the irradiated part tend to decrease. If the amount of the acid diffusion controller is less than 0.1 parts by weight, the pattern shape or dimensional fidelity as a resist may be lowered depending on the process conditions.

Surfactant A surfactant exhibiting an effect of improving the coatability and striation of the radiation-sensitive resin composition, the developability as a resist, and the like can be blended.
Examples of such surfactants include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenol ether, polyoxyethylene n-nonylphenol ether, polyethylene glycol dilaurate, polyethylene glycol dilaurate. Examples of commercially available products include F-top EF301, EF303, EF352 (manufactured by Tochem Products), Megafax F171, F173 (above, Dainippon Ink & Chemicals, Inc.) )), Fluorad FC430, FC431 (above, manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, the SC105, the SC106 (manufactured by Asahi Glass Co., Ltd.), KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, no. 95 (manufactured by Kyoeisha Chemical Co., Ltd.).
These surfactants can be used alone or in admixture of two or more.
The blending amount of the surfactant is preferably 2 parts by weight or less per 100 parts by weight of the acid-dissociable group-containing resin in the positive radiation sensitive resin composition.

Sensitizer A sensitizer can be mix | blended with a radiation sensitive resin composition. Preferred sensitizers include, for example, carbazoles, benzophenones, rose bengals, anthracene and the like.
These sensitizers can be used alone or in admixture of two or more. The amount of the sensitizer is preferably 50 parts by weight or less per 100 parts by weight of the acid-dissociable group-containing resin in the positive resist composition.

Solvent The radiation-sensitive resin composition is dissolved in a solvent so that the concentration of the total solid content is usually 0.1 to 50% by weight, preferably 1 to 30% by weight. For example, it is prepared as a composition solution by filtering with a filter having a pore size of about 0.2 μm.
Examples of the solvent used for the preparation of the composition solution include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, ethylene glycol mono-n-butyl ether acetate and the like. Glycol monoalkyl ether acetates; propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether; propylene glycol dimethyl ether, propylene glycol diethyl Ether, propylene glycol di-n-propyl ether, propylene Propylene glycol dialkyl ethers such as recall di-n-butyl ether; propylene glycol monoalkyl such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-n-butyl ether acetate Ether acetates; lactate esters such as methyl lactate, ethyl lactate, n-propyl lactate, i-propyl lactate; n-amyl formate, i-amyl formate, ethyl acetate, n-propyl acetate, i-propyl acetate, Aliphatic carboxylates such as n-butyl acetate, i-butyl acetate, n-amyl acetate, i-amyl acetate, i-propyl propionate, n-butyl propionate and i-butyl propionate Ethyl hydroxyacetate, ethyl 2-hydroxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutyrate, ethyl methoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, Methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, 3-methyl-3-methoxybutyl Other esters such as butyrate, methyl acetoacetate, ethyl acetoacetate, methyl pyruvate, ethyl pyruvate; aromatic hydrocarbons such as toluene, xylene; methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, 2-heptanone, 3-heptanone, 4 -Ketones such as heptanone and cyclohexanone; Amides such as N-methylformamide, N, N-dimethylformamide, N-methylacetamide, N, N-dimethylacetamide and N-methylpyrrolidone; Lactones such as γ-butyrolacun Is mentioned.
These solvents can be used alone or in admixture of two or more.

Formation of resist pattern When forming a resist pattern from a radiation-sensitive resin composition, the composition solution prepared as described above is applied by appropriate application means such as spin coating, cast coating, roll coating, etc. For example, it is applied onto a substrate such as a silicon wafer or a wafer coated with aluminum, and in some cases, a heat treatment (hereinafter referred to as “PB”) is performed at a temperature of about 70 ° C. to 160 ° C. to form a resist film. After that, drawing is performed by irradiating radiation, preferably EB. The drawing conditions are appropriately selected according to the composition of the radiation sensitive resin composition, the type of each additive, and the like.

In the present invention, in order to stably form a high-precision fine pattern, a heat treatment (hereinafter referred to as “PEB”) is performed at a temperature of 50 to 200 ° C., preferably 70 to 160 ° C. for 30 seconds or more after irradiation. ) Is preferable. In this case, when the temperature of the PEB is less than 50 ° C., there is a possibility that the variation in sensitivity depending on the type of the substrate is widened.
Then, a predetermined resist pattern is formed by developing with an alkali developer usually at 10 to 50 ° C. for 10 to 200 seconds, preferably at 15 to 30 ° C. for 15 to 100 seconds.
Examples of the alkali developer include alkali metal hydroxide, aqueous ammonia, mono-, di- or tri-alkylamines, mono-, di- or tri-alkanolamines, heterocyclic amines, and tetraalkyls. Alkaline compounds such as ammonium hydroxides, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo- [4.3.0] -5-nonene are usually used. An alkaline aqueous solution dissolved so as to have a concentration of 1 to 10% by weight, preferably 1 to 5% by weight, particularly preferably 1 to 3% by weight is used.
In addition, a water-soluble organic solvent such as methanol or ethanol or a surfactant can be appropriately added to the developer composed of the alkaline aqueous solution.
In forming the resist pattern, a protective film or an antistatic film can be provided on the resist film in order to prevent the influence of basic impurities contained in the environmental atmosphere and the charge in the film.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.
Here,% and parts are based on weight unless otherwise specified.

Synthesis Example 1: Synthesis of acid-dissociable group-containing resin (B-1) 97 g of 4-acetoxystyrene, 48 g of 4-t-butoxystyrene, 5 g of styrene, 6 g of azobisisobutyronitrile and 0.9 g of t-dodecyl mercaptan After being dissolved in 150 g of propylene glycol monomethyl ether, the polymerization was carried out for 16 hours while maintaining the reaction temperature at 70 ° C. in a nitrogen atmosphere. After the polymerization, the reaction solution was dropped into a large amount of n-hexane to coagulate and purify the resulting copolymer.
Next, 150 g of propylene glycol monomethyl ether was added to the copolymer, and then 300 g of methanol, 70 g of triethylamine, and 12 g of water were further added, and a hydrolysis reaction was performed for 8 hours while refluxing at the boiling point. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the obtained copolymer was dissolved in acetone, then dripped into a large amount of water to solidify, and the resulting white powder was filtered and filtered at 50 ° C. under reduced pressure. Dried overnight.
The obtained copolymer had an Mw of 16,000 and an Mw / Mn of 1.7. As a result of ¹³ C-NMR analysis, a copolymerization mole of 4-hydroxystyrene, 4-t-butoxystyrene and styrene was obtained. The ratio was 65: 30: 5. Mw and Mw / Mn are a high-speed GPC device (model “HLC-8120”) manufactured by Tosoh Corporation and two GPC columns (trade name “G2000H _XL ” manufactured by Tosoh Corporation); “G3000H _XL ”; , “G4000H _XL ”; 1), and measured by gel permeation chromatography (GPC) using monodisperse polystyrene as a standard under the analysis conditions of a flow rate of 1.0 ml / min, elution solvent tetrahydrofuran, and column temperature of 40 ° C. .
This compound is referred to as acid dissociable group-containing resin (B-1), and the chemical structural formula thereof is shown below.

Synthesis Example 2: Synthesis of acid-dissociable group-containing resin (B-2) 4-Acetoxystyrene 102 g, t-butyl acrylate 27 g, styrene 21 g, azobisisobutyronitrile 7 g and t-dodecyl mercaptan 1 g were mixed with propylene glycol. After dissolving in 225 g of monomethyl ether, polymerization was carried out for 16 hours while maintaining the reaction temperature at 70 ° C. in a nitrogen atmosphere. After the polymerization, the reaction solution was dropped into a large amount of n-hexane to coagulate and purify the resulting copolymer.
Next, 150 g of propylene glycol monomethyl ether was again added to the copolymer, and then 300 g of methanol, 75 g of triethylamine and 14 g of water were further added, and a hydrolysis reaction was performed for 8 hours while refluxing at the boiling point. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the obtained copolymer was dissolved in acetone, then dripped into a large amount of water to solidify, and the resulting white powder was filtered and filtered at 50 ° C. under reduced pressure. Dried overnight.
The obtained copolymer had Mw of 11,500 and Mw / Mn of 1.6. As a result of ¹³ C-NMR analysis, the copolymerization mole of 4-hydroxystyrene, t-butyl acrylate and styrene was obtained. The ratio was 60:20:20. This copolymer is an acid-dissociable group-containing resin (B-2), and the chemical structural formula is shown below.

Synthesis Example 3: Synthesis of acid-dissociable group-containing resin (B-3) 96 g of 4-acetoxystyrene, 54 g of 1-ethyl-1-cyclopentyl acrylate, 6 g of azobisisobutyronitrile, 0.9 g of t-dodecyl mercaptan After being dissolved in 150 g of propylene glycol monomethyl ether, polymerization was carried out for 16 hours while maintaining the reaction temperature at 70 ° C. in a nitrogen atmosphere. After the polymerization, the reaction solution was dropped into a large amount of n-hexane to coagulate and purify the resulting copolymer.
Next, 150 g of propylene glycol monomethyl ether was added to the copolymer, and then 300 g of methanol, 70 g of triethylamine, and 12 g of water were further added, and a hydrolysis reaction was performed for 8 hours while refluxing at the boiling point. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the obtained copolymer was dissolved in acetone, then dripped into a large amount of water to solidify, and the resulting white powder was filtered and filtered at 50 ° C. under reduced pressure. Dried overnight.
The obtained copolymer had Mw of 15,000 and Mw / Mn of 1.6. As a result of ¹³ C-NMR analysis, copolymerization of 4-hydroxystyrene with 1-ethyl-1-cyclopentyl acrylate The molar ratio was 65:35. This copolymer is an acid-dissociable group-containing resin (B-3), and the chemical structural formula is shown below.

Synthesis Example 4: Synthesis of acid-dissociable group-containing resin (B-4) 4-acetoxystyrene 88.5 g, 2-methyl-2-adamantyl acrylate 61.5 g, azobisisobutyronitrile 5.5 g, t- After dissolving 0.8 g of dodecyl mercaptan in 150 g of propylene glycol monomethyl ether, polymerization was carried out for 16 hours while maintaining the reaction temperature at 70 ° C. in a nitrogen atmosphere. After the polymerization, the reaction solution was dropped into a large amount of n-hexane to coagulate and purify the resulting copolymer.
Next, 150 g of propylene glycol monomethyl ether was added to the copolymer, and then 300 g of methanol, 65 g of triethylamine, and 11.5 g of water were further added, and a hydrolysis reaction was performed for 8 hours while refluxing at the boiling point. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the obtained copolymer was dissolved in acetone, then dripped into a large amount of water to solidify, and the resulting white powder was filtered and filtered at 50 ° C. under reduced pressure. Dried overnight.
The obtained copolymer had Mw of 16,000 and Mw / Mn of 1.8. As a result of ¹³ C-NMR analysis, copolymerization of 4-hydroxystyrene and 2-methyl-2-adamantyl acrylate The molar ratio was 65:35. This copolymer is an acid-dissociable group-containing resin (B-4), and the chemical structural formula is shown below.

Synthesis Example 5: Synthesis of acid-dissociable group-containing resin (B-5) 25 g of 4-hydroxystyrene and 4-t-butoxystyrene copolymer (Nippon Soda VPT1503S) having a molar ratio of 90:10 were mixed with n-butyl acetate. After dissolving in 100 g and bubbling with nitrogen gas for 30 minutes, 3.3 g of ethyl vinyl ether was added, 1 g of pyridinium 4-toluenesulfonate was added as a catalyst, and the reaction was allowed to proceed at room temperature for 12 hours. Thereafter, the reaction solution was dropped into a 1 wt% aqueous ammonia solution to precipitate the resin, filtered, and dried overnight in a vacuum dryer at 50 ° C.
The obtained copolymer had Mw of 13,000 and Mw / Mn of 1.01, and as a result of ¹³ C-NMR analysis, 4-hydroxystyrene was 67 mol%, and the hydrogen atom of the phenolic hydroxyl group was ethoxyethyl. The copolymer was a copolymer having 23 mol% of units substituted with groups and 10 mol% of 4-t-butoxystyrene. This copolymer is an acid-dissociable group-containing resin (B-5), and the chemical structural formula is shown below.

The materials used in each example and comparative example are shown below.
(A) Acid generator A-1; N- (trifluoromethylsulfoniumoxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide A-2; triphenylsulfonium trifluoromethanesulfonate A-3; (4-hydroxyphenyl) diphenylsulfonium trifluoromethanesulfonate A-4; 2,4,6-trimethylphenyldiphenylsulfonium 4-trifluoromethylbenzenesulfonate A-5; diphenyliodonium trifluoromethanesulfonate A-6; bis (1,4-dioxaspiro [4.5] undecan-7-sulfonyl) diazomethane A-7; (4-t-butoxycarbonylmethoxyphenyl) diphenyltrifluoromethanesulfonate A-8; (4-t-butoxycarbonylmethoxy) Enyl) diphenylnonafluoro-n-butanesulfonate A-9; (4-t-butoxycarbonylmethoxyphenyl) diphenyl 4-trifluoromethylbenzenesulfonate A-10; (4-t-butoxycarbonylmethoxyphenyl) diphenyl 2- ( Bicyclo [2.2.1] heptan-2-yl) -1,1,2,2-tetrafluoroethanesulfonate (B) Acid dissociable resin B-1; 4-hydroxystyrene / 4-t-butoxystyrene / Styrene (molar ratio 65/30/5) copolymer (Mw; 16000, Mw / Mn; 1.7) (Synthesis Example 1)
B-2; 4-hydroxystyrene / t-butyl acrylate / styrene (molar ratio 60/20/20) copolymer (Mw; 11500, Mw / Mn; 1.6) (Synthesis Example 2)
B-3; 4-hydroxystyrene / 1-ethyl-1-cyclopentyl acrylate (65/35 in molar ratio) copolymer (Mw; 15000, Mw / Mn; 1.6) (Synthesis Example 3)
B-4; 4-hydroxystyrene / 2-methyl-2-adamantyl acrylate (65/35 in molar ratio) copolymer (Mw; 16000, Mw / Mn; 1.8) (Synthesis Example 4)
B-5; 4-hydroxystyrene / 4-ethoxyxyethylstyrene / 4-butoxystyrene (molar ratio 67/23/10) copolymer (Mw; 13000, Mw / Mn; 1.01) (Synthesis Example 5) )
(C) Acid diffusion controller C-1; N- (t-butoxycarbonyl) 2phenylbenzimidazole C-2; Nt-butoxycarbonyldicyclohexylamine C-3; Tri-n-octylamine (D) Solvent D -1; ethyl lactate D-2; propylene glycol monomethyl ether acetate

Examples 1-14 and Comparative Examples 1-5
The formulation of the Hoji type radiation sensitive resin composition is shown in Table 1 (however, in each table, parts are based on weight). Each component was mixed to obtain a uniform solution, and then filtered through a membrane filter having a pore size of 200 nm to remove foreign matters, thereby preparing a resist solution. Thereafter, these resist solutions were spin-coated on an 8-inch silicon wafer to form a resist film having a thickness of 200 nm. Subsequently, the resist film was irradiated with an electron beam using a simple electron beam drawing apparatus (manufactured by Hitachi, model “HL800D”, output: 50 KeV, current density: 5.0 ampere / cm ² ). After the irradiation, PEB was performed under the conditions shown in Table 2, and then development was performed at 23 ° C. for 60 seconds by the paddle method using an aqueous solution containing 2.38% by weight of tetramethylammonium hydroxide. Thereafter, it was washed with water for 30 seconds and dried to form a resist pattern. The resist composition was evaluated according to the following (1), (2) and (3). The results are shown in Table 2. In Tables 1 and 2, Examples 1 to 5 and Examples 8 to 14 are reference examples.
(1) Sensitivity When a resist film formed on a silicon wafer is irradiated with an electron beam, immediately subjected to PEB, developed with alkali, washed with water and dried to form a resist pattern. The exposure dose that the space pattern forms in a one-to-one line width was taken as the optimum dose, and this optimum dose was taken as the sensitivity.
(2) Resolution The minimum dimension (nm) of the resist pattern that is resolved when irradiated with the optimum dose is taken as the resolution.
(3) LWR (Line roughness characteristics)
The line width defined as the above resolution is 50 μm in the length direction of the line pattern, and any 30 points are laterally measured by the scanning electron microscope for semiconductor S-9220 Hitachi high resolution FEB length measuring device, and the dispersion of the line width variation is dispersed. Calculated by 3σ.

  Since the resist composition of the present invention is excellent not only in the sensitivity and LWR at the time of pattern formation of the resist composition but also in the resolution, it is useful for the formation of fine patterns by electron beams, EUV and X-rays. Therefore, the resist composition of the present invention is extremely useful as a chemically amplified resist for manufacturing semiconductor devices, which is expected to be further miniaturized from now on.

Claims (2)

A radiation-sensitive acid generator (A), an acid-dissociable group-containing resin (B) which is alkali-insoluble or hardly soluble in alkali and easily soluble in alkali by the action of an acid, and an acid diffusion controller (C) A positive radiation sensitive resin composition patterned using electron beam, X-ray, or extreme ultraviolet radiation,
The radiation sensitive acid generator (A) is 20 parts by weight or more and 80 parts by weight or less, and the acid diffusion controller (C) is 0.1 parts per 100 parts by weight of the acid dissociable group-containing resin (B). From 1 to 1 part by weight,
The acid-dissociable group-containing resin (B) contains a repeating unit represented by the following formula (1) and a repeating unit represented by the following formula (3).

(In Formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a monovalent organic group, s is an integer of 1 to 3, t is an integer of 0 to 3, R ² present may be the same as or different from each other. In Formula (3), R ⁶ represents a hydrogen atom or a methyl group, R ⁷ represents a t-butyl group, a 1-methyl-1-cyclopentyl group, Represents a 1-ethyl-1-cyclopentyl group)   2. The positive feeling according to claim 1, wherein the radiation-sensitive acid generator (A) is at least one compound selected from a sulfonyloxyimide compound, a sulfonium salt compound, an iodonium salt compound, and a diazonium salt compound. Radiation resin composition.